Nasal polyps (NP) are the most common disease of the nose, with a prevalence of 4% of the population. In patients with this disease, the nasal cavity is gradually filled with polyps and they can only breathe through their mouths; in extreme cases, the external nose is deformed and enlarged by the growing polyps, commonly known as “frog nose” (Figure 1). As the disease causes severe nasal congestion, pus and blood, headache and loss of smell (Figure 2), it seriously affects the quality of life of patients and causes a heavy social and economic burden, becoming one of the chronic diseases that endanger the health of the public. The annual cost of treatment in the United States is as high as $8.6 billion (2011), and the average annual cost of treatment per patient is $2609 (2002); the average cost for European patients is €1861 (2002). On the one hand, nasal polyp disease causes a heavy socioeconomic burden, and on the other hand, its treatment status is far from satisfactory. Nasal polyps can only be treated surgically when they become severe, but since a significant proportion of nasal polyps are prone to recurrence, patients need repeated surgeries, even up to twenty times, which makes them unbearable.
So what causes nasal polyps to recur so easily? A recent study by my group published in the 2015 American Journal of Rhinology and Allergology (AJRA) may partially explain the recurrence of nasal polyps (Figure 3). In this study, polypectomy was performed in 387 patients with nasal polyps, and all excised polyp specimens were analyzed pathologically and given reasonable medication and close follow-up after surgery. After two years, 45% (173) of the patients had recovered well and the polyps did not recur. However, another 55% (214) of the patients with nasal polyps successively developed recurrence within two years. We found significant differences in the microscopic world of polyps between the recurrence and non-recurrence groups. The recurrent nasal polyp tissue tended to be microscopically visible with a large increase in a specific type of inflammatory cell, the eosinophil (Figure 4). And with the increase of this cell, the patient’s risk of recurrence increases. When the ratio of eosinophils to all inflammatory cells in a nasal polyp exceeds 27%, the patient’s risk of recurrence within two years is over 95%.
This study will rewrite our existing clinical treatment habits: in the past, most doctors would operate on nasal polyps directly and send the postoperative polyp specimens to the pathology department for pathological diagnosis, and the final pathological diagnosis of “nasal polyps” would merely confirm the preoperative assumptions. If the patient is cured after surgery, all are happy, but if the polyp recurs soon, the patient is likely to blame the doctor’s skill or unsuccessful surgery. The relevance of this study is that both the doctor and the patient can predict before the surgery whether the nasal polyp will recur or not. The method is simple: a small piece of polyp tissue is taken from the patient’s nasal cavity before surgery and sent for pathological examination. If the eosinophil count in the polyp tissue is more than 27%, the patient is basically a recurrence prone case. If the symptoms are not serious and do not affect the life, you can choose conservative drug treatment to see the effect, not to do, because it may recur; on the other hand: if the polyp grows bigger and bigger, and the symptoms are so serious that you have to do surgery, what should we do? Well, since we know that it is easy to recur after surgery, and this recurrence is caused by the patient’s special constitution, it is necessary to carry out strict medication and regular follow-up after surgery to combat this special constitution, to control the recurrence of polyps, to preserve the “victory results” and to avoid or reduce re-operation. As the saying goes, “the wind rises at the end of the weeds and the waves rise between the waves”, a tiny detail often determines the course of things. Similarly, microscopic cellular analysis of a small piece of polyp tissue before surgery can also allow us to predict the outcome of the surgery!
Figure 1. The external nose is deformed by the polyp filled in the nasal cavity, which is called “frog nose”.
Figure 2. The nasal cavity is filled with translucent polyps.
Figure 3. Our study was published in the 2015 AJRA Journal (The American Journal of Rhinilogy and Allergy).
Figure 4. When eosinophils exceed 27% in nasal polyp tissue, the risk of recurrence exceeds 95% in this patient. The large number of cells with red-stained cytoplasm in the figure are eosinophils.